Back to Exams

Posted in Education, Maynooth on October 26, 2021 by telescoper

After a welcome break for yesterday’s traditional Hallowe’en Bank Holiday it’s time today to embark on the tradition of the Writing of the First Semester Examinations. I have to come up with four papers (two main exams for January and two repeat exams for next August) by next week, complete with solutions. I always find it very difficult writing examinations, perhaps for the same reason that I find devising clues for crosswords much harder than solving the puzzles. In this world there are setters and solvers and I definitely count myself among the latter.

Anyway, it has been decided that the exams in January will be of the traditional type, sat in person in an Examination Hall, as opposed to the online version we have been using since May 2020. I feel I should point out that was the plan this time last year too, but it didn’t work out that way in the end because of climbing Covid-19 cases. I wouldn’t rule out an abrupt volte-face this year either. The situation is not looking good at all. In fact it looks very much like last year…

I think the “open-book” style of our online examinations had much to recommend it, with an emphasis on problem solving. The one flaw is that we can’t really do anything about collusion when students are sitting remotely and can exchange messages with each other in the absence of an invigilator. I never saw any evidence of significant collusion in the exams I graded, but there’s no denying it was a possibility that we couldn’t negate.

Interestingly, the student representatives present at our Department Meeting a couple of weeks ago indicated that their discussions with other students came out heavily in favour of on-campus examinations. As a result only one of our examinations – for an advanced postgraduate module with very few students taking it – will be of the online “open-book” style. The rest, including my own, will be written and marked on paper. That’s the plan, anyway…

I don’t know how to teach…

Posted in Education, Maynooth with tags , , , , , on October 25, 2021 by telescoper

Making use of this Bank Holiday Monday morning to tidy up some things on my computer I realized I had bookmarked this short clip of Richard Feynman answering a question about teaching. I clearly intended to blog about it at some point but forgot to do so, so I’m correcting that now.

Feynman was of course a renowned lecturer both for university students and for public audiences. I think one of the things that made him so successful is that he liked talking about his subject and liked being the centre of attention; people who like neither of those things are unlikely to make good lecturers!

But the thing that really struck me about what he says in this clip is near the beginning where he says he thinks the way to approach teaching is “be chaotic” to “use every possible way of doing it”. Now some of us are occasionally chaotic by accident, but I think there is a great deal of truth in what he says. I also agree with him when he says “I really don’t know how to do it..” I don’t either

If you start from the premise that every student is different, and will consequently learn in a different way, then you have to accept that there is no one unique style of teaching that will suit everyone. It makes sense therefore to try different kinds of things: worked examples, derivations, historical asides, question-and-answer sessions, and so on. And we shouldn’t rely exclusively on lectures: there must be a range of activities: problems classes, tutorials, supplementary reading, etc. With a bit of luck the majority of your class will find something that stimulates and/or enlightens them.

The point about using every possible method at your disposal has become especially relevant now that we have had about 18 months’ experience of online teaching. I feel very strongly that we should make recordings of lectures routinely available to all students, not as a replacement for the “live” experience but to add to the set of resources a student can draw on. The same goes for other things which came into regular use doing our online period, such as printed lecture notes (again, not as a replacement for a student’s own notes but as a supplement).

I think it also helps to acknowledge that what you can actually achieve in a lecture is very limited: you shouldn’t be simply trying to “deliver” material for later regurgitation. You should be pointing out the particularly interesting aspects, explaining why they are particularly interesting, and what things students should follow up in private study where in textbooks and on the net they will find yet more different ways of approaching the subject.

After over thirty years of teaching have come to the conclusion that the main purpose of university education is to convince students that their brain is more than simply a memory device, i.e. that it can also be used for figuring things out. I’m not saying that a good memory is worthless. It can be extremely useful and memory skills are important. I’m just saying that the brain can do other things too. Likewise, examinations should not be simple memory tests. Sadly school education systems seem to be focussed on coaching students passing exams by rote learning.

We see particular evidence of this in physics, with many students afraid to even attempt to solve problems they haven’t seen before. One infers that they passed exams by simply memorizing answers to questions very similar to those on the paper. Our job is to remove that fear, not by pretending that physics is easy, but by giving students the confidence to start believing that they can do things that they previously thought were too difficult. In other words, university education is often about undoing some of the limitations imposed on students by their school education.

Back to lecturing, there are some obvious basics which lecturers need to do in order to teach competently, including being prepared, talking sufficiently loudly, writing clearly (if relevant), and so on. And of course turning up at the right theatre at the right time. But there are also those things that turn mere competence into excellence. Of course there are many ways to lecture, and you have to put your own personality into what you do, but the main tips I’d pass on to make your lectures really popular can be boiled down into the Three Es. I add that these are things that struck me while watching others lecture, rather than me claiming to be brilliant myself (which I know I’m not). Anyway, here we go:

Enthusiasm. The single most obvious response on student questionnaires about lecturing refers to enthusiasm. My take on this is that we’re all professional physicists, earning our keep by doing physics. If we can’t be enthusiastic about it then it’s clearly unreasonable to expect the students to get fired up. So convey the excitement of the subject! I don’t mean by descending into vacuous gee-whizz stuff, but by explaining how interesting things are when you look at them properly as a physicist, mathematics and all.

Engagement. This one cuts both ways. First it is essential to look at your audience, ask questions, and make them feel that they are part of a shared experience not just listening to a monologue. The latter might be fine for a public lecture, but if a teaching session is to be successful as a pedagogical exercise it can’t be passive. And if you ask a question of the audience, make your body language tell them that it’s not just rhetorical: if you don’t look like you want an answer, you won’t get one. More importantly, try to cultivate an atmosphere wherein the students feel they can contribute. You know you’ve succeeded in this when students point out mistakes you have made. On the other hand, you can’t take this too far. The lecturer is the person who is supposed to know the stuff so fundamentally there’s no symmetry between you and the audience. You have to be authoritative, though that doesn’t mean you have to behave like a pompous schoolmaster. Know your subject, explain it well and you’ll earn respect without needing to bluster.

Entertainment. As I said above, lecturing is very limited as a way of teaching physics. That is not to say that lectures don’t have a role, which I think is to highlight key concepts and demonstrate their applicability;  the rest, the details, the nuts and bolts are best done by problem-based learning. I therefore think it does no harm at all if you make your lectures fairly light on detail and (with reason) enjoyable as pieces of entertainment. By all means introduce the odd joke, refer to surprising examples, amusing analogies, and so on.  As long as you don’t overdo it, you’ll find that a bit of light relief will keep the attention levels up. A key element of this is spontaneity. A lecture should appear as if it develops naturally, in an almost improvised fashion. Of course your spontaneity will probably have to  be very carefully rehearsed, but the sense of a live performance always adds value. A lecture should be a happening, not just a presentation. Lecture demonstrations also play this role, although they seem to be deployed less frequently  nowadays than in the past. Being a showman doesn’t come naturally to everyone, and the audience will know if you’re forcing it so don’t act unnaturally, but at the very least try to move about. Believe me, watching a lecturer drone on for an hour while rooted to the spot is a very tedious experience (especially on a video recording). You’d be surprised how much difference it makes if you can convey at least the impression of being alive.

On this last point, I’ll offer a few quotes from a physicist who definitely knew a thing or two about lecturing, Michael Faraday. First, his opinion was that the lecturer should not be

…glued to the table or screwed to the floor. He must by all means appear as a body distinct and separate from the things around, and must have some motion apart from that which they possess.

Conventional wisdom nowadays suggests that one should take breaks in lectures to stop students losing concentration. I’m not sure I agree with this, actually. It’s certainly the case that attention will flag if you persist with a dreary monotone for an hour, but  I think a lecture can have a natural dynamic to it which keeps the students interested by variation rather than interruption. Faraday also thought this.

A flame should be lighted at the commencement and kept alive with unremitting splendour to the end…I very much disapprove of breaks in the lecture.

Finally, here is one of my all-time  favourite physics quotes, Faraday’s take on the need for lectures to be entertaining:

..for though to all true philosophers science and nature will have charms innumerable in every dress, yet I am sorry to say that the generality of mankind cannot accompany us one short hour unless the path is strewn with flowers.

R.I.P. Bernard Haitink (1929-2021)

Posted in Music with tags , , on October 24, 2021 by telescoper

Renowned conductor Bernard Haitink passed away on 21st October at the age of 92. It’s hard to pick one piece to commemorate such a distinguished career in music so I’m not going to try to be objective. Some time ago I bought the complete set of Mahler Symphonies performed by the Royal Concertgebouw Orchestra in 1966 with Haitink at the helm and I think their performance of Mahler Symphony No. 3 is up there with the very best.

It’s interesting that as recently as 2018, another performance of Mahler 3 directed by Haitink won the BBC Recording of the Year. There is also a complete live performance from 1983 on Youtube which I was tempted to post here but the whole Symphony is about 100 minutes long so I decided instead to just post an excerpt which, fortunately, someone has already put on Youtube.

Here’s just one movement – the sixth and last – from that epic work. This movement is marked langsam which basically means “slow” but I think many conductors take this movement too slowly. Haitink for me judges the pace perfectly. There’s an overwhelming sense of catharsis at the climax of this movement.

R.I.P. Bernard Haitink (1929-2021)

Bank Holiday Break

Posted in Biographical, Maynooth on October 23, 2021 by telescoper

So here we are then, five weeks of teaching over, we have reached the mid-term break. I actually thought it was quite unusual to reach study week after 5/12 of the Semester rather than half, but it seems it happened as recently as two years ago. The pandemic has played havoc with my powers of recollection as well as other things. Anyway, this Monday (25th October) is a Bank Holiday in Ireland. The last Monday of October (Lá Saoire i mí Dheireadh Fómhair), or the Halloween Holiday (Lá Saoire Oíche Shamhna), is always a national holiday here, although Halloween itself isn’t until next Sunday.

I’ve got a big backlog of work things to do, but I can’t face it right now so I’m going to take the long weekend off and use Tuesday to Friday to try to tackle the to-do list (apart from Wednesday, when I have to attend a Conferring Ceremony).

In the meantime I will be doing nothing more strenuous than a bit of gentle gardening, including clearing away the leaves and tackling the last bit of ivy threatening to invade my house.

On the subject of gardening, I’ve noticed that I’ve got a fine crop of toadstools on the back lawn. I don’t know enough about fungi to know whether they are toxic, edible or even hallucinogenic, though I think if they were edible the birds would have a go at them. Any experts who can identify the type shown please feel free to let me know!

It’s always puzzled me how many people thing that there must be something wrong with their garden if there are toadstools in it. As far as I’m concerned they are part of the natural ecosystem so I just let them grow. I find them quite fascinating. They only live a few weeks so will disappear in due course without any intervention from me.

Chalk and Talk

Posted in Biographical, Education, Maynooth with tags , , , , on October 22, 2021 by telescoper

Today is the last day of teaching ahead of next week’s mid-term break. As it happens I did two consecutive lectures from 11-1 today instead of the usual one from 12-1 because of a rearrangement necessitated by a staff absence. I don’t mind admitting that I’m looking forward to a bit of a pause during Study Week, before embarking on the remaining 7 teaching weeks of the Semester.

The room I give my 12-1 lecture in has a chalkboard but the one for the 11-12 slot only has a whiteboard. The downside of the whiteboard is that it is almost impossible to make a lecture recording because the contrast is too low. I was happy to move to the usual room for the second one, which isn’t great either but at least has a decent blackboard.

A still from one of last year’s Engineering Maths lectures from home…

I know people think I am very old fashioned in persistently using a chalkboard. They also find it quite amusing that I bought one especially so I could do lectures from home using it. It’s far easier to get a decent contrast than using a whiteboard and I find that standing up and walking around allows me to communicate more effectively, at a decent pace and with a reasonable amount of energy. Most importantly of all I think it’s important for the students to see a process unfolding.

It’s proving much more difficult to provide decent quality lecture recordings on campus than at home because of the lack of decent camera facilities, but I’m doing the best I can.

Anyway, I was pleased to find a recent article about why Mathematics professors at Stanford University still use chalkboards. I agree with everything in it and will continue to use chalk and talk as long as I can. The way things are going with Covid-19 I may even be using the one at home again before too long…

The Irish Svarabhakti

Posted in Biographical, History with tags , , , , on October 21, 2021 by telescoper

One of the things I’ve picked up about Hiberno-English pronunciation is that Irish people tend to pronounce the English word “film” as something like “fillum”. I always thought this was just a sort of mannerism, but it turns out to be quite a bit more interesting than that.

The general term for the addition of an extra sound to the pronunciation of a word is epenthesis and it is a fairly common feature of many languages. The extra sound can be added at the beginning, at the end or in the middle. The latter case is specifically called anaptyxis or sometimes svarabhakti, which is a Sanskrit word specifically for the insertion of a vowel after the letter l or r before another consonant.

In most cases these extra vowel sounds are inserted to aid pronunciation, If you think about it the mouth and tongue have to do something quite complicated to get from l to m and a nice easy “uh” sound makes the transition simpler.

The Celtic group of languages was the first wave of Indo-European languages, to sweep across Europe. I blogged about this here. It seems the idiosyncratic pronunciation of “film” as “fillum” (which, I’m told, is also in widespread use in India) is a relic of the Irish language’s distant origins in Sanskrit, having no doubt crossed into Hiberno-English at a time when Irish was more widely spoken than it is now.

Another topical example is the name Colm (as in Colm Tóibín), which is pronounced “Collum” (or, depending on dialect, something more like “Cullum”).

Anaptyxis isn’t restricted to Irish, of course. There are examples in English. Who could forget the form favoured by football supporters? Engerland! Engerland! Engerland! (I don’t remember the rest of the lyrics to that song…)

From Maynooth to SFI

Posted in Maynooth, Science Politics with tags , , , on October 20, 2021 by telescoper

Last month I mentioned that I attended an event to mark the departure of Professor Philip Nolan at the end of his term as President of Maynooth University. Over drinks afterwards he wasn’t very forthcoming about what he was planning to do next, but yesterday news broke that he is to become the Director General of Science Foundation Ireland.

Amusingly, I see the slogan for SFI is ‘For What’s Next…’

Congratulations to Professor Nolan on this appointment! For the last 18 months, as well as being President of Maynooth University, he has been chairing the Epidemiological Modelling effort as part of National Public Health Emergency Team dealing with Covid-19. He won’t be starting his new job until January, so is now probably taking a bit of a rest.

The job at SFI will be a big challenge. Science in Ireland is in a dire state of under-investment, especially in basic (i.e. fundamental) research. Until recently SFI really only funded applied science, but recently seemed to have shifted its emphasis a little bit in its latest strategic plan.

Currently Ireland spends just 1.1% of its GDP on scientific research and development and SFI currently has a heavy focus on applied research (i.e. research aligned with industry that can be exploited for short-term commercial gain). This has made life difficult for basic or fundamental science and has driven many researchers in such areas abroad, to the detriment of Ireland’s standing in the international scientific community.

The new strategy, which covers the period from now to 2025, plans for 15% annual rises that will boost the agency’s grant spending — the greater part of the SFI budget — from €200 million in 2020 to €376 million by 2025. Much of this is focused in top-down manner on specific programmes and research centres but there is at least an acknowledgement of the need to support basic research, including an allocation of €11 million in 2021 for early career researchers. The overall aim is to increase the overall R&D spend from 1.1% of gross domestic product, well below the European average of 2.2%, to 2.5% by 2025.

Obviously this increase in funding is welcome and that is a big positive for the incoming Director General, but important strategic decisions will need to be taken about the overall balance of the programme. I wish Professor Nolan well as he takes over the helm.

New Publication at the Open Journal of Astrophysics

Posted in Open Access, The Universe and Stuff with tags , , , , , on October 20, 2021 by telescoper

Time to announce another publication in the Open Journal of Astrophysics. This one is the 13th paper in Volume 4 (2021) and the 44th in all.

The latest publication is entitled  The LSST-DESC 3x2pt Tomography Optimization Challengeand is in the folder marked Instrumentation and Methods for Astrophysics, and is especially relevant for cosmology. The paper is led by Joe Zuntz of the University of Edinburgh, and there are 27 authors altogether, scattered across the globe, representing the LSST Dark Energy Science Collaboration.

Here is a screen grab of the overlay which includes the abstract:

You can find the paper on the Open Journal of Astrophysics site here and can also read it directly on the arXiv here.

Revision of Lecter Notes

Posted in Film, The Universe and Stuff with tags , , , , , , , , on October 19, 2021 by telescoper

I’ve just finished my 11th Lecture on Mechanics and Special Relativity. The Tuesday lecture is in a 5pm to 6pm slot which means quite a few students need to leave early in order to get buses home. I try therefore to design it in such a way that the last 10 minutes or so is optional, so those that depart before the end don’t miss anything vital. Today I ended with a sort of philosophical aside about the nature of things versus how they interact with other things. I wrote about such thoughts already on this blog but that was almost a decade ago so I reckon enough time has elapsed for me to reiterate it here in a slightly modified form.

The text for this dissertation is a short speech by Hannibal Lecter from the film The Silence of the Lambs (1991), specifically the “quotation” from the Meditations of Roman Emperor and stoic philosopher>Marcus Aurelius.

The quotation by Lecter reads

First principles, Clarice. Simplicity. Read Marcus Aurelius. Of each particular thing ask: what is it in itself? What is its nature? What does he do, this man you seek?

I always felt this would make a good preface to a book on particle physics, playing on the word “particular”, but of course one has to worry about using part of a film script without paying the necessary copyright fee, and there’s also the small matter of writing the book in the first place.

Anyway, I keep the Penguin Popular Classics paperback English translation of the Meditations with me when I go travelling; I can’t read Greek, the language it was originally written in. It is one the greatest works of classical philosophy, but it’s also a collection of very personal thoughts by someone who managed to be an uncompromisingly authoritarian Emperor of Rome at the same time as being a humble and introspective person. Not that I have ever in practice managed to obey his exhortations to self-denial!

Anyway, the first point I wanted to make is that Lecter’s quote is not a direct quote from the Meditations, at least not in any English translation I have found. The nearest I could find in the version I own is Book 8, Meditation X:

This, what is it in itself, and by itself, according to its proper constitution? What is the substance of it? What is the matter, or proper use? What is the form, or efficient cause? What is it for in this world, and how long will it abide? Thus must thou examine all things that present themselves unto thee.

Or possibly, later on in the same Book, Meditation XII:

As every fancy and imagination presents itself to unto thee, consider (if it be possible) the true nature, and the proper qualities of it, and reason with thyself about it.

There are other translated versions to be found on the net (e.g. here), all similar. Thus Lecter’s reference is a paraphrase, but by no means a misleading one.

A more interesting comment, perhaps, relates to the logical structure of Lecter’s quote. He starts by asking about a thing “in itself”, which recalls the ding an sich of Immanuel Kant. The point is that Kant argued that the “thing in itself” is ultimately unknowable. Lecter continues by asking not what the thing (in this case a man) is in itself but what it (he) does, which is not the same question at all.

It has long struck me that this is similar to the way we work in physics. For example, we might think we understand a bit about what an electron is, but actually what we learn about is how it interacts with other things, which of its properties change and which remain the same, i.e. what it does. From such behaviour we learn about what attributes we can assign to it, such as charge, mass and spin, but we know these only through their interactions with other entities. The electron-in-itself remains a mystery.

This is true of mathematical objects too. Objects are defined to do certain things under certain operations. That is the extent of their definition. Physicists tend to think there is a reality beyond the mathematics used to represent it, but can we ever really know anything about that reality?

If the reference to mathematical physics all sounds a bit nerdy, then I’ll make the obvious point that it also works with people. Do we ever really know what another person is in himself or herself? It’s only through interacting with people that we discover anything. They may say kind or nasty things and perform good or evil deeds, or act in some other way that leads us to draw conclusions about their inner nature. But we never really know for sure. They might be lying, or have ulterior motives. We have to trust our judgement to some extent otherwise we’re forced to live in a world in which we don’t trust anyone, and that’s not a world that most of us are prepared to countenance.

Even that is similar to physics (or any other science) because we have to believe that, say, electrons (or rather the experiments we carry out to probe their properties) don’t lie. This takes us to an axiom upon which all science depends, that nature doesn’t play tricks on us, that the world runs according to rules which it never breaks.

Theoretical Astrophysics Job Opportunity in Cork

Posted in The Universe and Stuff on October 18, 2021 by telescoper

Just time today to pass on the news that the University of Cork is advertising a Lectureship in Theoretical Astrophysics “with a specialism in astrophysics, gravitational physics or cosmology (although outstanding candidates from any research area in astronomy can also apply)”. More details can be found here. The deadline for applications is 11th November.

I’m posting this information here to encourage cosmologists and gravitational physicists to apply because I would love to see the community in these areas grown in Ireland. This is a follow-up position to the Professorship in Astrophysics recently advertised.